Disadvantages of job enlargement:
1. Job enlargement tends to be a costly affair. Workers may require additional training for their enlarged jobs. Moreover, if the Job enlargement involves breaking up of existing production line of work system and redesigning a new system and training employees for it, the costs will be very substantial.
2. Productivity may fall in the short run, due to the introduction of the new system.
3. Employee unions often argue for increased pay because of the increased work hard.
4. Some jobs may still be routine and boring even after Job enlargement.